As expected by leading operators and vendors in NGMN (Next Generation Mobile Network) association, diverse applications or services are supposed to be provided by 5G networks. 5G will support numerous emerging use cases with a wide range of applications and variability of their performance requirements, for example, from delay-sensitive video applications to ultra-low latency, from high speed entertainment applications for use in a vehicle to mobility on demand for connected objects, and from best effort applications to reliable and ultra-reliable applications, such as those in the field of health and safety.
Furthermore, such diverse use cases will be delivered across a wide range of devices (e.g., smartphone, wearable, MTC (Machine Type Communications)) and across a highly heterogeneous environment. Obviously, different use cases may impose different requirements on future networks, for example, in terms of acceptable interruption time, reliability and availability, acceptable latency, data rate, as well as cost per user. It would be quite difficult or cost inefficient to deploy a common network to fulfill such extremely diverse requirements.
To resolve the problem, Ericsson proposed a concept of network slice to meet diverse requirements for various 5G use cases. Meanwhile, the concept of network slice is increasingly drawing attention in the NGMN association. A network slice supports a communication service of a particular connection type with a specific way of handling C(control)-plane and U(ser)-plane for the service.
In the IT industry, many OTT (Over-The-Top) service providers, such as Google, Apple, have already moved their applications onto a cloud infrastructure so that capacity of an application server can be flexibly scaled and dynamically deployed or migrated to a place that is more needed by users. Once an OTT application is deployed over the cloud, it is convenient for its OTT service provider to reselect an application server or move the application server workload across the distributed cloud infrastructure to serve mobile users in a more efficient manner.
To fulfill dynamic user requirements resulted from cloud based OTT applications, and also as inspired by great success of cloud technology in the IT world, the telecommunication industry is considering providing cloud based network services by the NFV (Network Function Virtualization) initiative at ETSI (European Telecommunication Standards Institute). NFV may transform the way that networks are built and operated by leveraging standard IT virtualization technology and consolidating various types of network equipments into “industry standard” servers. The NFV technology may make it more flexible and efficient to provide and operate a virtual mobile network service. With the quick development of cloud computing and NFV technology, it can be expected that more 5G network services will be deployed in a cloud environment in form of various network slices for agile operation and scaling to fulfill dynamic user requirements.
Meanwhile, as the penetration of various smart terminals (such as smart phone) and wearable devices (such as smart watch, Head Mounted Device (HMD)) increases worldwide and the interest in content-rich multi-media services (e.g. OTT video streaming services, virtual reality (VR), augmented reality (AR)) arises, this trend of rapidly increasing data traffic is expected to continue and accelerate. At the same time, there is a strong expectation to further improve the user experience of services like social networks, and to support vagarious use cases expected for 5G like Tactile Internet service.